use X-point psi to find plasma boundary for eqdsk, might need to check when...

use X-point psi to find plasma boundary for eqdsk, might need to check when limited. Use FPC for deafault Ip, closer to EQI/IDE

git-svn-id: https://spcsvn.epfl.ch/repos/TCV/gdat/trunk@9334 d63d8f72-b253-0410-a779-e742ad2e26cf